Sounds like you may have cold air blowing directly onto the Passport II display…The temp sensor is the little bump under the bottom ledge of the faceplate (just under the word AIRRRR)

If you can't direct the cold discharge air away from the display…You can install a remote sensor & place it in the return air path (usually right behind the return air grill) Once connected….The remote sensor will cancel out the display sensor.

Steve~

ScubaPete said:

Ok, that makes sense. There really isn't any air blowing on the display mounted sensor. I never removed or disconnected the display/control pad from the wall. But I was doing this troubleshooting with the circuit board laying right on top of the air handler unit. Would the cold right there screw this up?

Is the red square LED supposed to be lit?…Yes it indicates the board has power.

Does the remote sensor just plug into the existing jack? How much $?…It plugs into the Alt Air jack…A 7' sensor is $40.00

I think it's your only choice other than a $565.00 retrofit kit to the new Passport I/O system.

Steve~

ScubaPete said:

I think I will go with the remote sensor. So this will cancel out the temp sensor in the display/contol unit…Yes…does that mean that the displayed temp will be correct now if it is picking up from this new sensor?…

I can't guarantee that it will Pete…I can only say that it might & that it is a much cheaper option than a Retrofit kit, and that there may be a problem with the sensor in your Passport II display…If not, then there is a problem with your board reading that info from the temp sensor, and the only way to know that is to plug in a remote sensor or another Passport II.

If it does not solve the problem then you can use the remote sensor with a retrofit kit…I can say that it is a more accurate way of sensing temp…

 

I got your PM…The price is what I quoted above earlier plus freight (and sales tax if you are in Fl.) I don't discount orders under $500.00

I'm answering here so that others may see how to place an order…At this point…Just send me an e-mail thru the Contact Steve link at the top of any page (I'm working on an order form, but not done with it yet)

In that mail give me, What you are ordering, your mailing address, shipping address (If different, but No P.O. boxes for shipping) & phone #…Also how you would like it shipped (Ground, 2nd Day, or Next Day)…I will now have both ways to contact you if there is a question or problem…

I will then send you a return e-mail with my invoice and a secure link to pay on-line…When I receive payment conformation (usually the same day) I will have the order shipped and send another mail with tracking info…We ship UPS.

 

Thanks,

Steve~